I'm not sure this means anything---but---on my 2012 RT--I removed both the large plastic panels under the engine. One (left side) to assist in oil changes, and the other (right side) I just left off when I install the NBV highway pegs. While I never really had a huge heat issue with the machine, removing those plastic panels made a HUGE difference. Now when i ride, the temp gauge never goes past the quarter mark. I don't know if the 2013's have those panels, but in my opinion they are useless--try removing them and see what happens.
The issue with removing the 2013 RT's right hand underpanel is that there is a large electrical connector that will then be exposed to road spray. I resolved that issue by attaching a small aluminum shield.